On the surface of a glass plate or a ceramic plate, oxide layers having various functions according to the use are formed. For example, as glasses used for automobiles, vehicles, buildings, etc., a heat-reflective layer containing the oxide of titanium, cobalt, etc., is generally used for the purpose of reducing the cooling load, etc. Also, as glass substrates for various displays, an electrically conductive film comprising tin oxide, etc., is used from the necessity of element driving. These layers are frequently formed on only parts of the surface of a substrate for the necessity of each use described above.
In not only the use of display but also other uses of automobiles, buildings, etc., there is a case of requiring that the layer is partially formed. For example, in the case of using a heat-reflective glass for the back window of automobile, it is required that a layer is not formed on the glass surface adjacent to a high-mount stop lamp disposed in the inside of the back window of the automobile but a layer is formed on other portion of the glass surface for shielding heat rays while ensuring visibility of the lamp.
In such a case, a method of foaming the layer after previously applying masking to the necessary portion of the glass plate or a method of applying masking after forming a layer on the whole glass plate and removing the remaining unmasked portion of layer with a solvent, by releasing, or polishing, etc., is employed.
However, according to the conventional methods as described above, masking is required in any method, which is accompanied by complicated steps and operations, and thus the effective and ensure partial formation of layer has been difficult by the conventional methods.